Control switch arrangement for a spark plug ignition circuit



s. KOFINK 3,181,522

CONTROL SWITCH ARRANGEMENT FOR A SPARK PLUG IGNITION CIRCUIT Filed May2. 1960 United States Patent E 7,6 1 Claim. (Cl. 123-148) This inventionrelates generally to switch mechanisms and concerns in particular thecontrol of switches for electric circuits in power systems, such asheaters for automotive vehicles.

It is one of the objects of the invention to provide means afi'ordinghighly economical, very sensitive and positive control of a switchmechanism in an electric circuit to which any suitable consumer unit,such as a spark plug and like device of a combustion engine or likepower aggregate is connected.

It is another and important object of this invention to provide meansaiming at a switch control system of great simplicity, which takes uponly a minimum of space and whose driving power is derived from theexhaust or compressed gas of an internal combustion engine.

Yet a further object of the invention resides in the provision of meansconducive to a very compact and eflicacious control system of theaforesaid type, in which a predetermined pressure (low pressure,overpressure and like working conditions) influences or regulates theoperation of an electric switch system which is operatively connected toa power source or aggregate.

In known heaters, in particular in heaters used in automotive vehicleswith spark ignition, the circuit breakers are either operated by themotor shaft which drives the blower, or by parts of the internalcombustion engine. These devices, however, require complicated andadditional transmission parts which take up considerable space.

It is therefore still another object of the present inven tion toprovide means overcoming these and other disadvantages of the prior art.

The problem underlying the invention is to provide means devising aspark ignition device devoid of rotating parts, which problem is solvedby the provision of movable parts of a circuit breaker, which parts arecontrolled by the pulses produced by an internal combustion engine inthe gas-conducting ducts thereof. These pulses may be derived from thesuction line as well as from the exhaust line of the engine.

In accordance with the invention, a membrane box or housing is connectedto a branch of the exhaust gas conducting line, the membrane containedin said bOX being exposed to the influences of pulsating gases andcooperating With the movable part of the interrupter or circuit breaker.

In the membrane housing or box the counter contact for the circuitbreaker may be disposed in a manner known per se. Instead of a membranea check valve or like device may be provided, whereby the valve plate isequipped with a movable contact part pertaining to the circuit breaker.

In both these solutions the movably arranged contact parts or carriersof the circuit breaker may be connected with the housing part andthereby readily grounded.

It is therefore still another object of the invention to provide meansredounding to a quick-acting control mechanism of the type hereindisclosed, which is devoid of any mechanical drive or actuatingelements, is not subjected to any frictional wear and compliessatisfactorily with heavy operational conditions inherent in combustionengines and like power aggregates.

These and other objects of the present invention will become furtherapparent from the following detailed description, reference being madeto the accompanying drawing, showing preferred embodiments of theinvention.

In the drawing:

FIG. 1 shows, schematically and in section, an arrangement of amembrane-controlled circuit breaker and a circuit diagram connectedtherewith; and

FIG. 2 shows a view similar to that of FIG. 1, whereby themembrane-controlled circuit breaker is replaced by a valve-controlledinterrupter.

Referring now more specifically to the drawing, there is disclosed inFIG. 1 a branch connection 1a connected to the exhaust gas line 1 of acombustion engine (not shown).

Joined to the branch connection 1a is a membrane housing 2 containingthe membrane proper 2a. Membrane member 2a carries centrally thereof amovable contact element 3 which is located opposite and normally inspaced relation to the counter contact element Sax seated on the upperhousing part 2b.

The upper housing part 2b is made from electrically non-conductivematerial, for example, plastic or plastic composition.

The membrane member 2a consists of a thin sheet material assuming abellows form and responding to vibrations of a controlled stream ofexhaust gas entering through an opening 1c of nozzle 1b, thereby flowingin the direction according to arrow A for actuation of membrane member2a for closing contacts 3, 3a.

When gas flows in the direction of arrow B, a separation of the contacts3, 3a is eliectuated. As soon as the contacts 3-, 3a are separated andthus brought into inoperative position, the pressure pulses from theexhaust gas are communicated to the partial stream flowing throughopening 10 and influence the membrane 2a.

The circuit through primary winding 4, which is grounded at one side, isthen closed and a high current surge produced which induces in thesecondary Winding 4a a current which then discharges at theschematically shown electrodes 5a, 5b of the spark plug 5.

The interrupter counter contact 3a establishes then across the movablecontact 3 a connection via the conductive membrane disk or member 2a andthe lower part of the housing 2, which, in turn, is grounded by thebranch part In of the exhaust.

A similar control arrangement or device is constituted by the circuitbreaker construction of FIG. 2. As here shown, instead of a membrane,there is provided a check valve 6 having a valve plate 6c which appliesunder pressure of spring 6a against an open work support element 6b.

This element carries the movable circuit breaker contact 3'. The countercontact 3" is held by an insulating screw arrangement 7 which is made ofplastic or plastic composition and hence is separated from the groundcontacting parts of check valve 6, while the movable contact 3 isgrounded across spring 6a.

Thus it will be seen that pulses emanating from the exhaust or like gasconduit 1 are communicated via branch 1a in accordance with the arrowsto the valve place 6c in a manner similar to membrane member 20, ashereinabove stated with respect to FIG. 1.

It can thus be seen that there has been provided, according to thisinvention, a switch control arrangement for operating an electriccircuit for the spark plug ignition of a power aggregate equipped with aconduit for fluid flow; a housing, means responsive to fluid pressureand including a displaceable member located in said housing and incommunication with said conduit, and circuit breaker means in saidignition circuit for opening and closing the same, respectively, saidbreaker means including two cooperable contacts, respectively, supportedin said housing, one of said contacts being movable to and fro the othercontact and being operatively connected with said displaceable member,the other of said contacts being stationary and carried by a part ofsaid housing, which is electrically insulated from the remainder of saidhousing.

Various changes and modifications may be made without departing from thespirit and scope of the present invention and it is intended that suchobvious changes and modifications be embraced by the annexed claim.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

An interrupter switch for the electrical spark ignition of a devicehaving an exhaust gas conduit with a pulsating exhaust gas flowtherethrough during operation of the device, comprising a closedhousing, an extension conduit connected into the lower end of saidhousing and into said exhaust gas conduit, a member extending acrosssaid extension conduit adjacent the connection to said exhaustgasconduit and having an orifice opening therethrough, a movable memberdisposed across said housing exposed to the pulsating gas flow from saidextension conduit, a spark ignition circuit, a first contact connectedin said spark ignition circuit and mounted in a fixed location in saidhousing on a side thereof opposite from said extension conduit, and asecond contact connected in said spark ignition circuit carried by saidmovable member on the same side of said housing as said first contactand being displaceable with said movable member into and out ofengagement with said first contact in accordance with the pulsating gasflow in said conduit.

References Cited by the Examiner UNITED STATES PATENTS RICHARD B.WILKINSON, Primary Examiner.

MAX L. LEVY, WALTER STOLWEIN, Examiners.

